Bi-directional communications on an electrical secondary networked distribution system

ABSTRACT

Mechanisms for bi-directional communications on an electrical secondary networked distribution system are disclosed. A first edge node control device (ENCD) receives, via an off-grid communications interface, a message. The first ENCD is communicatively coupled to the secondary networked distribution system, and the secondary networked distribution system provides electricity to a plurality of consuming endpoints. The method further includes retransmitting, in response to receipt of the message, by the first ENCD on the secondary networked distribution system, the message to a plurality of internal node control devices communicatively coupled to the secondary networked distribution system at a plurality of locations.

RELATED APPLICATIONS

This application claims the benefit of provisional patent applicationNo. 62/086,980, filed on Dec. 3, 2014, entitled “SYSTEM AND METHOD FORSECONDARY GRID COMMUNICATIONS,” the disclosure of which is herebyincorporated herein by reference in its entirety.

TECHNICAL FIELD

The embodiments relate generally to electrical distribution systems and,in particular, to bi-directional communications on an electricalsecondary networked distribution system.

BACKGROUND

Electrical power is typically delivered over transmission lines to oneor more primary distribution systems. The voltage on a primarydistribution system is lower than the voltage on the transmission lines.For example, the voltage on the transmission lines may be between 138kiloVolts (kV) and 765 kV, and the voltage on the primary distributionsystem may be between about 2 kV and 35 kV. The primary distributionsystem delivers the electrical power to one or more secondarydistribution systems. The secondary distribution systems are at a lowervoltage than the primary distribution system. For example, the voltageon a secondary distribution system may be below about 2 kV. Somecustomers that require substantial amounts of power may be coupleddirectly to the primary distribution systems. However, the vast majorityof customers, both residential and commercial, are coupled to asecondary distribution system.

There are different types of secondary distribution systems, including,for example, a secondary radial distribution system and a secondarynetworked distribution system. A networked distribution system is morecostly than a radial distribution system but offers high reliabilitybecause multiple feeders from the primary distribution system provideredundant electrical power to each consumer on the secondary networkeddistribution system. If one feeder goes down, the consumers continue toreceive power provided by the other feeder. In dense urban metropolitanareas, secondary networked distribution systems are commonly used sothat large numbers of consumers are not negatively impacted should afeeder go down.

In a secondary networked distribution system there are a number oflocations, referred to herein as grid nodes (or “nodes”), whereelectrical control or monitoring (ECOM) devices, such as protectiondevices, switch devices, and electrical transformation devices, provideneeded functionality to the secondary networked distribution system. Insome areas, there may be a substantial number of such ECOM devices, andsome or all of such ECOM devices may be housed in respective undergroundvaults. It is common that the ECOM devices are not coupled tocommunications lines, such as copper or fiber lines, via which the ECOMdevices could communicate with other devices outside of the vault.

However, it often would be desirable to implement bi-directionalcommunications with the ECOM devices to monitor and control the ECOMdevices without requiring a human to go to a location of the equipmentand enter an underground vault. Moreover, it may be desirable to controlone or more of the ECOM devices located at different locationssubstantially concurrently, or in a predefined sequence. However,running communications lines to the ECOM devices may be prohibitivelyexpensive, and wireless communications with ECOM devices in undergroundvaults may be impossible. While some mechanisms exist for communicatingwith the ECOM devices from the primary distribution system to thesecondary distribution system, such mechanisms are relatively costly andoften require the installation of additional equipment at thetransformers. Moreover, signals on underground power lines bleed offmuch more rapidly than overhead lines, greatly reducing signal range.

SUMMARY

The embodiments relate to bi-directional communications on an electricalsecondary networked distribution system. The embodiments facilitatecommunications between an edge node control device coupled to asecondary networked distribution system and a plurality of internal nodecontrol devices coupled to the secondary networked distribution system.The internal node control devices may be coupled to the secondarynetworked distribution system at locations where electrical control ormonitoring is located. The edge node control device receives a messagefrom an off-grid interface and, based on the message, communicates aninstruction over the secondary networked distribution system to one ormore internal node control devices.

Among other advantages, the embodiments facilitate bi-directionalcommunications without a need for relatively expensive equipment that iscapable of communicating from high voltage lines to low voltage linesthrough a transformer, or communicating from low voltage lines to highvoltage lines through a transformer, because all communications canoccur within the secondary networked distribution system.

In one embodiment, a method for communicating on a secondary networkeddistribution system is provided. The method includes receiving, by afirst edge node control device (ENCD) via an off-grid communicationsinterface, a message. The first ENCD is communicatively coupled to thesecondary networked distribution system, and the secondary networkeddistribution system provides electricity to a plurality of consumingendpoints. The method further includes retransmitting, in response toreceiving the message, by the first ENCD on the secondary networkeddistribution system, the message to a plurality of internal node controldevices communicatively coupled to the secondary networked distributionsystem at a plurality of locations.

In one embodiment, the first ENCD is located at a grid node, and thegrid node houses an electrical control or monitoring (ECOM) devicecoupled to the secondary networked distribution system. The first ENCDis communicatively coupled to the ECOM device and is configured to, inresponse to receiving the first message, send a signal to the ECOMdevice to cause the ECOM device to alter or monitor an electricalcharacteristic of the secondary networked distribution system.

In one embodiment, the ECOM device comprises one of a transformer, aswitch, a fuse, or a monitoring device.

In one embodiment, a plurality of ENCDs receive the messagesubstantially concurrently, and the plurality of ENCDs retransmit, onthe secondary networked distribution system, the message to theplurality of internal node control devices communicatively coupled tothe secondary networked distribution system at the plurality oflocations.

In one embodiment, the method further includes determining that theplurality of internal node control devices received the message.

In another embodiment, a system for communicating on a secondarynetworked distribution system is provided. The system includes an edgenode control device that comprises an on-grid communications interfaceconfigured to be communicatively coupled to the secondary networkeddistribution system. The secondary networked distribution system isconfigured to provide electricity to a plurality of consuming endpoints.The edge node control device further includes an off-grid communicationsinterface configured to communicate via an off-grid communicationstechnology. A processing device is communicatively coupled to the ongrid-communications interface and the off-grid communications interface,and is configured to receive, via the off-grid communications interface,a message. The processing device is further configured to, in responseto receiving the message, retransmit on the secondary networkeddistribution system the message to a plurality of internal node controldevices communicatively coupled to the secondary networked distributionsystem at a plurality of locations.

Those skilled in the art will appreciate the scope of the disclosure andrealize additional aspects thereof after reading the following detaileddescription of the embodiments in association with the accompanyingdrawing figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawing figures incorporated in and forming a part ofthis specification illustrate several aspects of the disclosure and,together with the description, serve to explain the principles of thedisclosure.

FIG. 1 is a block diagram of a system in which embodiments may bepracticed;

FIG. 2 is a flowchart illustrating a method for communicating on asecondary networked distribution system according to one embodiment;

FIG. 3 is a block diagram illustrating a message layout of a messageaccording to one embodiment.

FIGS. 4A-4B are block diagrams illustrating a communication of messageson a secondary networked distribution system according to oneembodiment;

FIGS. 5A-5C are block diagrams illustrating a store-and-forwardcommunication of messages on a secondary networked distribution systemaccording to another embodiment;

FIG. 6 is a block diagram illustrating a mechanism for determining thatedge node control devices (ENCDs) and internal node control devices(INCDs) have received a message according to one embodiment;

FIGS. 7A-7B are block diagrams illustrating a mechanism for determiningthat ENCDs and INCDs have received a message according to anotherembodiment;

FIGS. 8A-8B are block diagrams illustrating a mechanism forsynchronizing actions among multiple INCDs according to one embodiment;

FIG. 9 is a block diagram of a computing device according to oneembodiment; and

FIG. 10 is a block diagram of an edge node control device according toone embodiment.

DETAILED DESCRIPTION

The embodiments set forth below represent the information to enablethose skilled in the art to practice the embodiments and illustrate thebest mode of practicing the embodiments. Upon reading the followingdescription in light of the accompanying drawing figures, those skilledin the art will understand the concepts of the disclosure and willrecognize applications of these concepts not particularly addressedherein. It should be understood that these concepts and applicationsfall within the scope of the disclosure and the accompanying claims.

Any flowcharts discussed herein are necessarily discussed in somesequence for purposes of illustration, but unless otherwise explicitlyindicated, the embodiments are not limited to any particular sequence ofsteps. The use herein of ordinals in conjunction with an element issolely for distinguishing what might otherwise be similar or identicallabels, such as “first internal node control device” and “secondinternal node control device,” and does not imply a priority, a type, animportance, or other attribute, unless otherwise stated herein. The term“about” used herein in conjunction with a numeric value means any valuethat is within a range of ten percent greater than or ten percent lessthan the numeric value.

As used herein, the articles “a” and “an” in reference to an element inthe claims means one or more of the element, and does not imply only oneof the element.

The embodiments relate to bi-directional communications on an electricalsecondary networked distribution system. The embodiments facilitatecommunications between an edge node control device coupled to asecondary networked distribution system and a plurality of internal nodecontrol devices coupled to the secondary networked distribution system.The internal node control devices may be coupled to the secondarynetworked distribution system at locations where electrical control ormonitoring are located. The edge node control device receives from anoff-grid interface a message and, based on the message, communicates aninstruction over the secondary networked distribution system to one ormore internal node control devices. The edge node control device thendetermines that the one or more internal node control devices receivedthe instruction.

FIG. 1 is a block diagram of a system 10 in which embodiments may bepracticed. The system 10 includes an electrical power primarydistribution system 12 (hereinafter primary distribution system 12 forpurposes of brevity) and an electrical power secondary networkeddistribution system 14 (hereinafter secondary networked distributionsystem 14 for purposes of brevity). The primary distribution system 12receives electrical power from an electrical power transmission system(not illustrated). The primary distribution system 12 may distributeelectricity at any desired voltage, but generally the primarydistribution system 12 distributes electricity at a relatively highvoltage of, by way of non-limiting example, between about 2 kV and 35kV. The primary distribution system 12 provides electricity to one ormore secondary distribution systems, such as the secondary networkeddistribution system 14.

The secondary networked distribution system 14 may distributeelectricity at any desired voltage, but generally the secondarynetworked distribution system 14 distributes electricity at a relativelylow voltage of, by way of non-limiting example, below about 2 kV. In theUnited States, for example, the secondary networked distribution system14 typically distributes electricity at 120V, 240V, or 480V. Thesecondary networked distribution system 14 distributes electricity to aplurality of consuming endpoints 16. The consuming endpoints 16 maycomprise, for example, residences, commercial enterprises, and the like.While only two consuming endpoints 16 are illustrated in FIG. 1, it willbe appreciated that the secondary networked distribution system 14 couldprovide electricity to any number of consuming endpoints 16, and, inurban areas, may provide electricity to tens of thousands of consumingendpoints 16. Each consuming endpoint 16 may be coupled to the secondarynetworked distribution system 14 via a transformer 18 that steps thevoltage of the secondary networked distribution system 14 down to alower voltage, or, depending on the voltage of the secondary networkeddistribution system 14, may be directly coupled to the secondarynetworked distribution system 14 without a transformer 18.

The secondary networked distribution system 14 comprises a plurality ofexternal node control devices (ENCDs) 20 _(e) 1-20 _(e) 6 (generally,ENCDs 20 _(e)) and internal node control devices (INCDs) 20 _(i) 1-20_(i) 6 (generally, INCDs 20 _(i)). The ENCDs 20 _(e) and the INCDs 20_(i) are distant from one another and are located at corresponding nodes22 of the secondary networked distribution system 14. Note that forpurposes of clarity only some of the nodes 22 are labeled with elementreference numerals. Each node 22 is at a particular location 24 inparticular geographical area serviced by the secondary networkeddistribution system 14. Note that for purposes of clarity only some ofthe locations 24 are labeled with element reference numerals. The nodes22 identify locations 24 of the secondary networked distribution system14 where an electrical control or monitoring (ECOM) device 26 islocated. An ECOM device 26 can comprise any device that is configured tocontrol, alter, halt, or monitor the electrical power on the secondarynetworked distribution system 14. An ECOM device 26 may comprise, by wayof non-limiting example, a transformer, a switch, a fuse or a monitoringdevice. Note that for purposes of clarity only some of the ECOM devices26 are labeled with element reference numerals.

The phrase “networked distribution system,” as used herein refers to anelectrical power distribution system that receives electrical power frommultiple feeders 28-1-28-4 (generally, feeders 28) of the primarydistribution system 12, and thus multiple feeders 28 provide electricalpower to the same nodes 22. An advantage of a networked distributionsystem is that if one feeder 28 goes down and fails to provideelectrical power, the secondary networked distribution system 14continues to receive electrical power from other feeders 28 such thatthe consuming endpoints 16 are not impacted by the feeder 28 that wentdown. A disadvantage of a networked distribution system is the cost.Other distribution systems, such as radial distribution systems, areless expensive but fail to provide the redundancy provided by anetworked distribution system. A networked distribution system is oftenutilized in highly dense areas, such as urban areas of metropolitancities.

Each or many of the nodes 22 may include a transformer that steps downthe voltage from the primary distribution system 12 to the desiredvoltage of the secondary networked distribution system 14. Eachtransformer provides the stepped down voltage to an electrical grid 30of the secondary networked distribution system 14. For example, an ECOMdevice 26-1 (ED) may comprise a transformer that receives electricalpower from the feeder 28-1, steps down the voltage, and provides theelectrical power to the grid 30. Similarly, an ECOM device 26-2 maycomprise a transformer that receives electrical power from the feeder28-2, steps down the voltage, and provides the electrical power to thegrid 30. Each node 22 may contain any number of ECOM devices 26.

While, for purposes of illustration, the consuming endpoints 16 areillustrated as being coupled to the secondary networked distributionsystem 14 between two nodes 22, it will be appreciated that a consumingendpoint 16 may be coupled to the secondary networked distributionsystem 14 at a node 22.

The ENCD 20 _(e) 3 comprises a processing device 32, an off-gridcommunications interface 34 configured to communicate via an off-gridcommunications technology, and an on-grid communications interface 36_(e) configured to communicate over the grid 30 via an on-gridcommunications technology. The on-grid communications interface 36 _(e)may comprise an on-grid receiver module configured to receive messagesfrom the grid 30, and an on-grid transmitter module configured totransmit messages onto the grid 30. The off-grid communicationstechnology may utilize any suitable communication medium such as a wiredcommunication medium, a fiber communication medium, or a wirelesscommunication medium. The off-grid communications technology may utilizeany public or proprietary protocol for communications.

In this example, the ENCD 20 _(e) 3 communicates via the off-gridcommunications interface 34 with a network 38 to which a number of otherprocessing devices are coupled. In particular, a supervisory control anddata acquisition (SCADA) system 40, a feeder intelligence module (FIM)42, and a computing device 44 may be communicatively coupled to thenetwork 38. As will be described in greater detail herein, the ENCDs 20_(e) facilitate communications between one or more of the SCADA system40, the FIM 42, the computing device 44, and the INCDs 20 _(i). In oneembodiment, use of the SCADA system 40 may be avoided through themechanisms disclosed herein.

The ENCD 20 _(e) 3 is also communicatively coupled to an ECOM device 26located at the node 22 at which the ENCD 20 _(e) 3 is located. Thisrelationship may be referred to herein as a correspondence between theENCD 20 _(e) 3 and the particular ECOM device 26 at the same location,such that each ENCD 20 _(e) is communicatively coupled to acorresponding ECOM device 26 at the same location. The ENCD 20 _(e) 3 isconfigured to communicate with the corresponding ECOM device 26 via alocal communications interface 37 _(e) using any suitable communicationstechnology, such as, by way of non-limiting example, a wired or wirelesslocal area network. Thus, as will be described in greater detail herein,the ENCD 20 _(e) 3 may receive messages via the network 38 that directthe ENCD 20 _(e) 3 to communicate with the corresponding ECOM device 26.The communications may direct the ECOM device 26 to perform some action,alter some parameter of the ECOM device 26, request information from theECOM device 26, or any combination of the above. The ENCDs 20 _(e) 1, 20_(e) 2, and 20 _(e) 4-20 _(e) 6 are configured similarly to the ENCD 20_(e) 3, and are similarly communicatively coupled to a correspondingECOM device 26.

The INCD 20 _(i) 3 comprises a processing device 46 and an on-gridcommunications interface 36 _(i) configured to communicate over the grid30 via an on-grid communications technology. Unlike the ENCDs 20 _(e),the INCDs 20 _(i) may have no off-grid communications interface 34.Thus, in some embodiments, the INCDs 20 _(i) may communicate only overthe grid 30 via an on-grid communications technology. The INCD 20 _(i) 3is also communicatively coupled to and configured to communicate via alocal communications interface 37; with an ECOM device 26 co-locatedwith the INCD 20 _(i) 3 using any suitable communications technology,such as, by way of non-limiting example, a wired or wireless local areanetwork. The INCDs 20 _(i) 1, 20 _(i) 2, and 20 _(i) 4-20 _(i) 6 areconfigured similarly to the INCD 20 _(i) 3, and are similarlycommunicatively coupled to a corresponding ECOM device 26.

In practice, the nodes 22 may be located in protected locations toprevent tampering. In urban environments, the nodes 22 may be located inunderground vaults and may only be accessible via a manhole. Suchunderground vaults typically inhibit wireless communications withdevices above ground. Moreover, due to the prohibitive cost, undergroundvaults frequently do not have communication lines interconnecting theunderground vaults. Thus, providing communications to the equipment inthe underground vaults can be impossible, or, if available, is limitedto conventional on-grid communications mechanisms that communicate withthe secondary networked distribution system 14 via the primarydistribution system 12. Unfortunately, such conventional on-gridcommunications are relatively costly and have many limitations.Moreover, due to the physical expanse of the secondary networkeddistribution system 14, some nodes 22 may simply be out of signal reachof a transmitter located on the primary distribution system 12.

Among other features, the embodiments facilitate bi-directionalcommunications on the secondary networked distribution system 14. Suchbi-directional communications allow a device, such as the computingdevice 44, to control and/or monitor ECOM devices 26 located at each ofthe nodes 22. Such actions can comprise any suitable actions that theECOM devices 26 are configured to implement. Such actions may also becoordinated such that the ECOM devices 26 perform actions in aparticular sequence, or, the ECOM devices 26 may perform actionssubstantially concurrently.

In one embodiment, the ENCDs 20 _(e) are located at one or more nodes 22and coupled to an off-grid communications mechanism. For example, fiberor electrical lines may be run to the locations 24 at which the ENCDs 20_(e) are located. The number of locations 24 of the ENCDs 20 _(e) may bea relatively small fraction of the number of locations 24 that house theINCDs 20 _(i), such as 1/100th, 1/1000^(th), or 1/10th. Thus, costs torun external communications to the nodes 22 that house the ENCDs 20 _(e)are relatively minimal compared to the cost to run externalcommunications to all the nodes 22.

The ENCDs 20 _(e) communicate with the computing device 44, the SCADAsystem 40, and/or the FIM 42 via the respective off-grid communicationsinterface 34 and the network 38. For purposes of illustration, many ofthe embodiments will be discussed herein in the context of the computingdevice 44 initiating and controlling communications on the secondarynetworked distribution system 14 via the ENCDs 20 _(e); however, thefunctionality attributed to the computing device 44 may be implementedin one or more other devices, such as the SCADA system 40 and the FIM42. In one embodiment, the computing device 44 includes a processingdevice 48 and a memory 50. The memory 50 may include a message controlmodule 52 that implements some or all of the functionality describedherein with regard to the computing device 44. The message controlmodule 52 may comprise complex software instructions, circuitry, and/ora combination of software instructions and circuitry. In someembodiments, the message control module 52 may be implemented in anapplications-specific integrated circuit or a field programmable gatearray.

The memory 50 may also include a network topology 54. The networktopology 54 includes information regarding the ENCDs 20 _(e) and theINCDs 20 _(i), such as electronic device addresses of the ENCDs 20 _(e)and the INCDs 20 _(i) to which messages may be addressed, the ECOMdevices 26 in communication with the respective ENCDs 20 _(e) and theINCDs 20 _(i), locations of the ENCDs 20 _(e), INCDs 20 _(i), and theECOM devices 26, and the like.

The FIM 42 includes a processing device 56 and a memory 58. The FIM 42is communicatively coupled to the feeders 28, and thus can receiveon-grid communications from the ENCDs 20 _(e) and the INCDs 20 _(i).While downstream communications from higher voltage systems such as theprimary distribution system 12 to lower voltage distribution systemssuch as the secondary networked distribution system 14 can be relativelycostly and of limited effectiveness, upstream communications from thesecondary networked distribution system 14 to the primary distributionsystem 12 are typically less costly and are generally more effective.Accordingly, in some embodiments, as will be discussed in greater detailbelow, the ENCDs 20 _(e) and the INCDs 20 _(i) may send messages to themessage control module 52 via the FIM 42 to, in part, implement thebi-directional communications disclosed herein. As discussed above, insome embodiments the message control module 52 and the network topology54 may be implemented in the FIM 42 rather than the computing device 44.

Each feeder 28 may have three phases separated by 120 degrees. Suchphases are sometimes referred to as the “A phase,” the “B phase,” andthe “C phase.” In the secondary networked distribution system 14 the Aphases from each feeder 28 are connected together; the B phases areconnected together; and the C phases are connected together. Theseinterconnected phases facilitate parallel communication paths by whichan ENCD 20 _(e) or INCD 20 _(i) can send transmissions to the FIM 42.Moreover, these interconnected phases facilitate multiple communicationpaths between ENCDs 20 _(e) and INCDs 20 _(i).

In one embodiment, the ENCDs 20 _(e) and the INCDs 20 _(i) communicateover the grid 30 by an injection of a modulated current signal on one ormore phases of the secondary networked distribution system 14 duringmessage transmission, and by receipt of a modulated voltage signal onthe same one or more phases during message reception.

The injection of the modulated current signal on a phase or phasescreates a corresponding small modulated voltage signal or signals due tothe impedance of the phase, or phases, at the point of injection as seenby the transmitting ENCD 20 _(e) or INCD 20 _(i). This complex impedancevaries by frequency of transmission, by voltage and phase angle of themains power (for example, 120 volts, 240 volts, or 480 volts, at 50 Hz,60 Hz, 400 Hz, or others), and by the consuming loads on the associatedphase at the point of injection. It is this resultant modulated voltagesignal that is used by the ENCDs 20 _(e) and the INCDs 20 _(i) forreception.

Due to the interconnected nature of the phases of the secondarynetworked distribution system 14, both the modulated current signal andthe modulated voltage signal propagate along an origin phase, or phases,in all possible directions from the point of injection, as well as alongthe interconnected phases and along any cross-coupled communicationpaths. Signals along the interconnected phases are attenuated morequickly than along the origin phase, which can result in a need forsignal repeaters in some embodiments.

The current signal transmitted by either the ENCDs 20 _(e) or the INCDs20 _(i) propagates along the phase, or phases, and can be received atthe FIM 42 in a substation that provides power to the secondarynetworked distribution system 14 by reception and demodulation of thecurrent signal, or signals. The current signal, or signals, is availableat the FIM 42 by monitoring 5 ampere (A) current loops of substationprotection current transformers (CTs) which provide signal to aprotection relay system and/or the SCADA system 40. Each phase poweringthe secondary networked distribution system 14 has a corresponding CT.This monitoring can be achieved by placing a small signal CT on each ofthe 5 A current loops and providing the output of the small signal CTsdirectly to the FIM 42. The FIM 42 contains one or more demodulators inwhich each small signal CT is directly connected to the input of acorresponding demodulator.

Furthermore, due to the physical proximity of the phases to each other,the presence of three phase transformers and three phase consumingloads, and the frequency of transmission by each ENCD 20 _(e) or INCD 20_(i), the modulated current signal can be electrically or magneticallycross-coupled between phases. This further increases the number ofcommunication paths at the feeder level while also creating amultiplicity of communications paths at the phases of the secondarynetworked distribution system 14. Thus, cross-coupling, which isnormally a problem in communications systems, can be exploited in thesecondary networked distribution system 14.

The modulated current signal can be implemented using a variety ofmodulation and demodulation methodologies, including, but not limitedto: Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying(QPSK), Frequency Shift Keying (FSK), Multi-Frequency Shift Keying(MFSK), and the like. Likewise, multiple frequencies can be utilized,creating one or more discrete communications channels. The channel, orchannels, may be further segmented using such techniques such as TimeDivision Multiple Access (TDMA) implemented in a slotted structure, orin an un-slotted structure with a random transmission protocol such asAloha.

FIG. 2 is a flowchart illustrating a method for communicating on thesecondary networked distribution system 14 according to one embodiment.FIG. 2 will be discussed in conjunction with FIG. 1. The ENCD 20 _(e) 3receives, via the off-grid communications interface 34, a message fromthe computing device 44 (FIG. 2, block 1000). The message may beaddressed to a particular INCD 20 _(i), all INCDs 20 _(i), or a group ofINCDs 20 _(i). In this example, assume that the message is destined fortwo particular INCDs 20 _(i). The message may contain an action, or ascript of actions, that the two INCDs 20 _(i) are to perform. Inresponse to receipt of the message, the ENCD 20 _(e) 3 re-transmits themessage on the secondary networked distribution system 14 via theon-grid communications interface 36 _(e) (FIG. 2, block 1002). Theon-grid communications interface 36 _(e) may communicate over aparticular phase of the secondary networked distribution system 14, ormay communicate over all three phases of the secondary networkeddistribution system 14. The re-transmitted message may be identical tothe received message, or the ENCD 20 _(e) 3 may reformat the message fortransmission on the grid 30. Because the INCDs 20 _(i) are all coupledto the grid 30, the INCDs 20 _(i) all receive the message substantiallyconcurrently, such as within the amount of time it takes for a signal topropagate from the ENCD 20 _(e) 3 to the INCD 20 _(i) farthest from theENCD 20 _(e) 3.

It is determined that the two INCDs 20 _(i) to which the message wasdestined received the message (FIG. 2, block 1004). In one embodiment,the determination may be made by the computing device 44. As will bediscussed in greater detail herein, the determination may be made in anynumber of different ways. If it had been determined that the one or bothINCDs 20 _(i) had not received the message, the computing device 44 mayresend the message to the ENCD 20 _(e) 3 for retransmission on the grid30.

FIG. 3 is a block diagram illustrating a message layout 60 of a messageaccording to one embodiment. The message layout 60 may be utilized bythe computing device 44 to send messages to the ENCDs 20 _(e) and theINCDs 20 _(i). In this embodiment, the message layout 60 includes adevice address field 62 in which the computing device 44 may identifydevice addresses, or device identifiers, of particular ENCDs 20 _(e) andINCDs 20 _(i) to which the message may be specifically directed, ifappropriate. For example, the computing device 44 may desire that anaction be taken by one or more particular ENCDs 20 _(e) and/or INCDs 20_(i), but not all ENCDs 20 _(e) and INCDs 20 _(i). The computing device44 may then identify the particular ENCDs 20 _(e) and/or INCDs 20 _(i)via the device address field 62. In one embodiment, the computing device44 may utilize a broadcast device address in the device address field 62to indicate that the message is directed to all ENCDs 20 _(e) and INCDs20 _(i).

In some embodiments, multiple ENCDs 20 _(e) and/or INCDs 20 _(i) may beidentified by a particular group address in a group address field 64. Agroup address is associated with a particular set, or group, of ENCDs 20_(e) and/or INCDs 20 _(i) that may, for certain actions, operate inconjunction to cause the action to occur. The actions may be performedsubstantially concurrently or in a particular sequence. The phrase“substantially concurrently” refers to actions that take place within aperiod of time less than or equal to a time it takes for a messagetransmitted on the grid 30 to reach each of the ENCDs 20 _(e) and/orINCDs 20 _(i). Generally, such time is a function of the greatestdistance between any INCD 20 _(i) and the closest ENCD 20 _(e).

The computing device 44 may insert a unique message identifier (ID) in amessage ID field 66 to uniquely identify messages communicated on thegrid 30. In some embodiments, the ENCDs 20 _(e) and the INCDs 20 _(i)may use the unique message ID in acknowledgement responses to indicatesuccessful receipt of the message.

The computing device may insert a particular message in a message field68. The message may comport with any desired syntax and protocol knownby the ENCDs 20 _(e) and the INCDs 20 _(i). In one embodiment, a messagetype 70-1 includes an action or actions, or a script, and an indicationthat the action is to be taken or the script executed upon receipt(i.e., immediately). The script may comprise a listing of actions and,in some embodiments, may comprise a language syntax that includesconditions, branches, and the like to control which actions are to beperformed. The actions may include instructions or control signals thatthe respective ENCDs 20 _(e) and INCDs 20 _(i) send to a correspondingECOM device 26 co-located with the respective ENCDs 20 _(e) and INCDs 20_(i). Thus, the ENCDs 20 _(e) and the INCDs 20 _(i) may, in response tothe receipt of a message, control a corresponding ECOM device 26.

A message type 70-2 includes an action or actions, or a script, and anindication that the action is to be taken at a future time. The futuretime may be a relative time offset from the time of receipt of themessage, or may be a definite time. A message type 70-3 includes anaction or actions, or a script, and an indication that the action is tobe taken at a future event. It should be apparent that the messagelayout 60 is but one possible message layout, and the embodiments arenot limited to any particular message layout.

While any suitable scripting language may be utilized in theembodiments, generally, a scripting language (sometimes referred to as arules-based language) facilitates the transmission of a sequence ofcommands which are executed by a receiving ENCD 20 _(e) or INCD 20 _(i)upon an event or sequence of events, a particular date/time, acondition, or any combination thereof. Non-limiting examples of a scriptsyntax and commands are provided below.

The script command: “@T=X;S1=F” may be interpreted as: “At time X turnswitch 1 off.” The script command: “@V<125;S2=O” may be interpreted as:“When the voltage is less than 125 volts then turn switch 1 on.” Thescript command: “1@T>Y;2@V<120;S2=0” may be interpreted as: “If the timeis later than X and the voltage is less than 125 volts then turn switch2 on.” The script command: “@f=1200,ST=0” may be interpreted as: “Atreception of a 1200 Hz tone, set the time to zero.”

Multiple scripts may be sent to and retained by a receiving ENCD 20 _(e)or INCD 20 _(i). For example, the following scripts could be sent to areceiving ENCD 20 _(e) or INCD 20 _(i): “@T=X;S1=F. @V<125;S2=O.1@T>Y;2@V<120;S2=0. @f=1200,ST=0.” such that the actions discussed abovecould be performed at the appropriate time and/or event.

FIGS. 4A-4B illustrate a communication of messages on the secondarynetworked distribution system 14 according to one embodiment. In FIGS.4A-4B, and subsequent figures discussed herein, portions of the primarydistribution system 12 have been omitted solely for purposes of claritybut are functional in the embodiments as described above. FIGS. 4A-4Balso illustrate the nodes 22 a distance from the grid 30 solely tofacilitate discussion of message communications on the secondarynetworked distribution system 14. Thus, in operation, a portion of thegrid 30 is coupled to the ENCDs 20 _(e) and the INCDs 20 _(i), asindicated by the dashed lines and circles extending from each node 22 tothe grid 30.

For purposes of illustration, assume that the computing device 44communicates a message 72 to the ENCDs 20 _(e) at a time T1. The ENCDs20 _(e) receive the message 72 substantially concurrently. FIG. 4Billustrates each ENCD 20 _(e) retransmitting the message 72 on the grid30 beginning at a time T2 in response to receiving the message 72. TheENCDs 20 _(e) may communicate on the grid 30 using any desired protocolfor communicating on a shared medium, including, by way of non-limitingexample, a random transmission protocol, such as Aloha, or a slottedtransmission protocol, such as slotted Aloha. In some embodiments, wherea single ENCD 20 _(e) can reach all the INCDs 20 _(i) via the grid 30,the ENCD 20 _(e) may communicate messages individually to each INCD 20_(i). The retransmitted message 72 may be a copy of the message 72 ormay be reformatted by the ENCDs 20 _(e) prior to retransmission. Notethat because the grid 30 is a shared medium, the retransmitted message72 is received substantially concurrently by each of the INCDs 20 _(i).Note that each INCD 20 _(i) may receive the retransmitted message 72multiple times. Further note that the strength of the retransmittedmessage 72 may differ depending on the distance between the nearesttransmitting ENCD 20 _(e) and the respective INCD 20 _(i).

The message 72 may have been identified by the computing device 44 as abroadcast message that is destined for each INCD 20 _(i), may have beenaddressed to one or more specified INCDs 20 _(i), or may have beendirected to a group of INCDs 20 _(i) utilizing a group address. EachINCD 20 _(i) receives the retransmitted message 72, examines theretransmitted message 72 to determine whether the retransmitted message72 is intended for the INCD 20 _(i), and if so, performs the actionindicated in the retransmitted message 72.

FIGS. 5A-5B illustrate a store-and-forward communication of messages onthe secondary networked distribution system 14 according to anotherembodiment. Referring first to FIG. 5A, assume that, as illustrated inFIG. 4A, each ENCD 20 _(e) received the message 72 from the computingdevice 44. At a time T2, each ENCD 20 _(e) retransmits the message 72 onthe grid 30 in response to receiving the message 72. The retransmittedmessage 72 may be a copy of the message 72 or may be reformatted by theENCDs 20 _(e) prior to retransmission. Note that because the grid 30 isa shared medium, the retransmitted message 72 is received substantiallyconcurrently be each of the INCDs 20 _(i). Note that each INCD 20 _(i)may receive the retransmitted message 72 multiple times. Further notethat the strength of the retransmitted message 72 may differ dependingon the distance between the nearest transmitting ENCD 20 _(e) and therespective INCD 20 _(i).

Referring to FIG. 5B, after receiving the retransmitted message 72, theINCDs 20 _(i) 1 and 20 _(i) 4 again retransmit the message 72 on thegrid 30. The retransmitted message 72 is received by the INCD 20 _(i) 2,the INCD 20 _(i) 3, the INCD 20 _(i) 5, and the INCD 20 _(i) 6.Referring to FIG. 5C, after receiving the message 72, the INCDs 20 _(i)2 and 20 _(i) 5 again retransmit the message 72 on the grid 30. Thus, inthis embodiment, the message 72 is repeatedly propagated along the grid30 by the INCDs 20 _(i). This ensures that INCDs 20 _(i) farther from atransmitting ENCD 20 _(e) ultimately receive the message 72,irrespective of the distance of the INCD 20; from the nearest ENCD 20_(e). The ENCDs 20 _(e) may communicate on the grid 30 using any desiredprotocol for communicating on a shared medium, including, by way ofnon-limiting example, a random transmission protocol, such as Aloha, ora slotted transmission protocol, such as slotted Aloha.

While for purposes of illustration each downstream INCD 20 _(i) isillustrated as retransmitting the message 72, in other embodiments onlycertain INCDs 20 _(i) may retransmit the message 72. In particular, inone embodiment, it may be determined, based on testing the grid 30, thatcertain INCDs 20 _(i) will receive the retransmitted message 72 from theENCDs 20 _(e), and others, due to distance and/or noise, will not. Insuch situations, only particular INCDs 20 _(i) nearest those INCDs 20_(i) that do not receive the original message 72 may be configured toretransmit the message 72. For example, assume that, based onpredetermined testing of the grid 30, it is determined that the INCDs 20_(i) 1, 20 _(i) 2, 20 _(i) 4, and 20 _(i) 5 will receive theretransmitted message 72 with sufficient signal strength from theoriginal retransmissions of the ENCD 20 _(e), but that the INCDs 20 _(i)3, 20 _(i) 6 will not. It is further determined that the INCDs 20 _(i)3, 20 _(i) 6 do receive messages 72 retransmitted from the INCDs 20 _(i)2, 20 _(i) 5. In this situation, only the INCDs 20 _(i) 2, 20 _(i) 5 maybe configured to retransmit the message 72.

In another embodiment, the appropriate retransmission by the INCDs 20;may be determined dynamically or heuristically. In particular, based onacknowledgement messages (ACKs) and/or negative acknowledgement messages(NACKs) received from the INCDs 20 _(i) after the retransmission of amessage 72 from the ENCDs 20 _(e), the computing device 44 may determinewhich INCDs 20 _(i) routinely receive the initial retransmission of amessage 72 from the ENCDs 20 _(e), and which INCDs 20 _(i) do not. Thecomputing device 44 may access the network topology 54, determine whichINCDs 20 _(i) are closest to those INCDs 20; that do not receive theinitial retransmission of a message 72 from the ENCDs 20 _(e), and sendsuch closest INCDs 20 _(i) a configuration instruction that configuresthe INCDs 20 _(i) to retransmit messages 72 on the grid 30.

In some embodiments, the originating sender of the message 72, in theprevious examples the computing device 44, may determine whether theENCDs 20 _(e) and the INCDs 20 _(i) to which the message 72 was destinedreceived the message 72. In one embodiment, this determination may bemade using a negative acknowledgement by exception protocol, wherein thecomputing device 44 determines that the ENCDs 20 _(e) and the INCDs 20_(i) to which the message 72 was destined received the message 72,unless a NACK is sent from the ENCDs 20 _(e) and the INCDs 20 _(i).Thus, in this embodiment, if no NACK is received by the computing device44 within a predetermined timeframe, the computing device 44 makes adetermination that the ENCDs 20 _(e) and the INCDs 20 _(i) to which themessage 72 was destined received the message 72.

FIG. 6 illustrates a mechanism for determining that the ENCDs 20 _(e)and the INCDs 20 _(i) received a message 72 according to anotherembodiment. In this embodiment, each ENCD 20 _(e) and INCD 20 _(i) towhich the message 72 was destined sends an ACK 76 upon successfulreceipt of the message 72. The ACKs 76 may contain, for example, adevice ID identifying the particular INCD 20 _(i), as well as themessage ID of the message 72. In this example, assume that the message72 was identified as a broadcast message that was destined for each ENCD20 _(e) and INCD 20 _(i). Upon receiving the message 72, the INCDs 20_(i) send an ACK 76 over the grid 30 via the secondary networkeddistribution system 14 to the primary distribution system 12. The FIM 42monitors and analyzes signals on the primary distribution system 12 andreceives the ACKs 76. The FIM 42 may communicate the ACKs 76 to thecomputing device 44. The computing device 44 may maintain informationregarding each message ID and which INCDs 20 _(i) and ENCDs 20 _(e) havesent ACKs 76, and thereby may determine which INCDs 20 _(i) and ENCDs 20_(e) have received the message 72. While not illustrated in FIG. 6, eachENCD 20 _(e) may similarly communicate an ACK 76 over the grid 30 viathe secondary networked distribution system 14 to the primarydistribution system 12, or, alternatively, may send an ACK 76 directlyto the computing device 44 using respective off-grid communicationsinterfaces 34.

FIGS. 7A-7B illustrate a mechanism for determining that the ENCDs 20_(e) and the INCDs 20 _(i) have successfully received a message 72according to another embodiment. In this embodiment, assume again thatthe message 72 was identified as a broadcast message by the computingdevice 44 and was destined for each ENCD 20 _(e) and INCD 20 _(i). Asillustrated in FIG. 7A, upon receipt of the message 72, each INCD 20_(i) generates an ACK 76, as described above, and transmits the ACK 76onto the grid 30. In this embodiment, the ENCDs 20 _(e) receive the ACKs76. Referring to FIG. 7B, each ENCD 20 _(e) retransmits the ACKS 76 tothe computing device 44 using the off-grid communications interface 34.Note that while only the ENCDs 20 _(e) 1 and 20 _(e) 2 are illustratedas retransmitting the ACKs 76, the ENCDs 20 _(e) 3-20 _(e) 6 may alsoretransmit received ACKs 76. Because each ENCD 20 _(e) may be unaware ofwhich ACKs 76 are being retransmitted by the other ENCDs 20 _(e), thecomputing device 44 may receive multiple copies of an ACK 76 from thesame INCD 20 _(i).

FIGS. 8A-8B illustrate a mechanism for synchronizing actions amongmultiple INCDs 20 _(i) according to one embodiment. In this example,assume that the computing device 44 generates a message 72 destined forthe INCDs 20 _(i) 4, 20 _(i) 5. The message 72 identifies an action thatshould be taken by the INCDs 20 _(i) 4, 20 _(i) 5 substantiallyconcurrently. The ENCDs 20 _(e) receive the message and transmit themessage 72 onto the grid 30. The INCDs 20 _(i) 4 and 20 _(i) 5 receivethe message and may transmit ACKs 76, as discussed above, to indicatereceipt. The message 72, in this example, is a message type 70-3 (FIG.3) and indicates that the action should be performed by the INCDs 20_(i) 4, 20 _(i) 5 upon the occurrence of a future event. In thisexample, the future event is identified as the detection of a tone onthe grid 30. The INCDs 20 _(i) 4, 20 _(i) 5 listen, such as bymonitoring, to the grid 30 for the presence of the tone. FIG. 8Aillustrates the computing device 44 sending a message 72A that isdestined for the ENCD 20 _(e) 2. The message indicates that upon receiptof the message 72A, the ENCD 20 _(e) 2 should apply a tone to the grid30. FIG. 8B illustrates the ENCD 20 _(e) 2 receiving the message 72A andapplying a tone 78 to the grid 30. Because the grid 30 is a sharedmedium, the tone 78 is received by the INCDs 20 _(i) 4, 20 _(i) 5substantially concurrently. The INCDs 20 _(i) 4, 20 _(i) 5, in responseto detecting the presence of the tone 78 on the secondary networkeddistribution system 14, perform the action(s) designated in the message72A.

In other embodiments, the computing device 44 may send a series ofmessages to different ENCDs 20 _(e) and INCDs 20 _(i) that identifydifferent actions to be processed in sequence. The communication of suchmessages and determinations of receipt of such messages may beaccomplished by one or more of the methods discussed above. Each messagemay designate that the respective action be performed at a particulartime, and each time may differ to ensure the actions are performed in aproper sequence. To ensure proper coordination, the ENCDs 20 _(e) andthe INCDs 20 _(i) may periodically synchronize internal clocks so thatsuch clocks are within a predetermined synchronization. Suchsynchronization may be accomplished in any desired manner.

FIG. 9 is a block diagram of the computing device 44 according to oneembodiment. The computing device 44 may comprise any computing orprocessing device capable of including firmware, hardware, and/orexecuting software instructions to implement the functionality describedherein, such as a computer server, workstation, or the like. In someembodiments, the computing device 44 may be a special-purpose computingsystem designed to implement communications power system communicationsas disclosed herein. The computing device 44 includes the processingdevice 48, the system memory 50, and a system bus 80. The system bus 80provides an interface for system components including, but not limitedto, the system memory 50 and the processing device 48. The processingdevice 48 can be any commercially available or proprietary processor.

The system bus 80 may be any of several types of bus structures that mayfurther interconnect to a memory bus (with or without a memorycontroller), a peripheral bus, and/or a local bus using any of a varietyof commercially available bus architectures. The system memory 50 mayinclude non-volatile memory 82 (e.g., read-only memory (ROM), erasableprogrammable read-only memory (EPROM), electrically erasableprogrammable read-only memory (EEPROM), etc.) and/or volatile memory 84(e.g., random-access memory (RAM)). A basic input/output system (BIOS)86 may be stored in the non-volatile memory 82, and may include basicroutines that help to transfer information between elements within thecomputing device 44. The volatile memory 84 may also include ahigh-speed RAM, such as static RAM for caching data.

The computing device 44 may further include or be coupled to acomputer-readable storage 88, which may comprise, for example, aninternal or external hard disk drive (HDD) (e.g., enhanced integrateddrive electronics (EIDE) or serial advanced technology attachment(SATA)), HDD (e.g., EIDE or SATA) for storage, flash memory, or thelike. The computer-readable storage 88 and other drives associated withcomputer-readable media and computer-usable media may providenon-volatile storage of data, data structures, computer-executableinstructions, and the like. Although the description ofcomputer-readable media above refers to an HDD, it should be appreciatedby those skilled in the art that other types of media that are readableby a computer, such as Zip disks, magnetic cassettes, flash memorycards, cartridges, and the like, may also be used in the exemplaryoperating environment, and further, that any such media may containcomputer-executable instructions for performing novel methods of thedisclosed architecture.

A number of modules can be stored in the computer-readable storage 88and in the volatile memory 84, including an operating system 90 and oneor more program modules 92, which may implement the functionalitydescribed herein in whole or in part. It is to be appreciated that theembodiments can be implemented with various commercially availableoperating systems 90 or combinations of operating systems 90.

All or a portion of the embodiments may be implemented as a computerprogram product stored on a transitory or non-transitory computer-usableor computer-readable storage medium, such as the computer-readablestorage 88, which includes complex programming instructions, such ascomplex computer-readable program code, configured to cause theprocessing device 48 to carry out the steps described herein. Thus, thecomputer-readable program code can comprise software instructions forimplementing the functionality of the embodiments described herein whenexecuted on the processing device 48. The processing device 48, inconjunction with the program modules 92 in the volatile memory 84, mayserve as a controller for the computing device 44 that is configured to,or adapted to, implement the functionality described herein.

The computing device 44 may also include a communications interface 94suitable for communicating with the network 38.

FIG. 10 is a block diagram of an ENCD 20 _(e) according to oneembodiment. The ENCD 20 _(e) may comprise any computing or processingdevice capable of including firmware, hardware, and/or executingsoftware instructions to implement the functionality described herein.In some embodiments, the ENCD 20 _(e) may be a special-purpose computingdevice designed to implement communications power system communicationsas disclosed herein. The ENCD 20 _(e) includes the processing device 46,a system memory 100, and a system bus 102. The system bus 102 providesan interface for system components including, but not limited to, thesystem memory 100 and the processing device 46. The processing device 46can be any commercially available or proprietary processor.

The system bus 102 may be any of several types of bus structures thatmay further interconnect to a memory bus (with or without a memorycontroller), a peripheral bus, and/or a local bus using any of a varietyof commercially available bus architectures. The system memory 100 mayinclude non-volatile memory 104 (e.g., read-only memory (ROM), erasableprogrammable read-only memory (EPROM), electrically erasableprogrammable read-only memory (EEPROM), etc.) and/or volatile memory 106(e.g., random-access memory (RAM)). A basic input/output system (BIOS)108 may be stored in the non-volatile memory 104, and may include thebasic routines that help to transfer information between elements withinthe ENCD 20 _(e). The volatile memory 106 may also include a high-speedRAM, such as static RAM for caching data.

The ENCD 20 _(e) may further include or be coupled to acomputer-readable storage 110, which may comprise, for example, aninternal or external hard disk drive (HDD) (e.g., enhanced integrateddrive electronics (EIDE) or serial advanced technology attachment(SATA)), HDD (e.g., EIDE or SATA) for storage, flash memory, or thelike. The computer-readable storage 110 and other drives associated withcomputer-readable media and computer-usable media may providenon-volatile storage of data, data structures, computer-executableinstructions, and the like. Although the description ofcomputer-readable media above refers to an HDD, it should be appreciatedby those skilled in the art that other types of media which are readableby a computer, such as Zip disks, magnetic cassettes, flash memorycards, cartridges, and the like, may also be used in the exemplaryoperating environment, and further, that any such media may containcomputer-executable instructions for performing novel methods of thedisclosed architecture.

A number of modules can be stored in the computer-readable storage 110and in the volatile memory 106, including an operating system 112 andone or more program modules 114, which may implement the functionalitydescribed herein in whole or in part. It is to be appreciated that theembodiments can be implemented with various commercially availableoperating systems 112 or combinations of operating systems 112.

All or a portion of the embodiments may be implemented as a computerprogram product stored on a transitory or non-transitory computer-usableor computer-readable storage medium, such as the computer-readablestorage 110, which includes complex programming instructions, such ascomplex computer-readable program code, configured to cause theprocessing device 46 to carry out the steps described herein. Thus, thecomputer-readable program code can comprise software instructions forimplementing the functionality of the embodiments described herein whenexecuted on the processing device 46. The processing device 46, inconjunction with the program modules 114 in the volatile memory 106, mayserve as a controller for the ENCD 20 _(e) that is configured to, oradapted to, implement the functionality described herein.

The ENCD 20 _(e) may also include the local communications interface 37_(e) that is configured to communicate with the corresponding ECOMdevice 26, the off-grid communications interface 34 that is configuredto communicate with the network 38, and the on-grid communicationsinterface 36 _(e) that is configured to communicate with the grid 30 ofthe secondary networked distribution system 14.

An INCD 20 _(i) may be configured similarly to that discussed above withrespect to the ENCD 20 _(e), except the INCD 20 _(i) may not have anoff-grid communications interface 34.

Those skilled in the art will recognize improvements and modificationsto the preferred embodiments of the disclosure. All such improvementsand modifications are considered within the scope of the conceptsdisclosed herein and the claims that follow.

What is claimed is:
 1. A method for communicating on a secondarynetworked distribution system, comprising: receiving, by a first edgenode control device (ENCD) via an off-grid communications interface, amessage, the first ENCD communicatively coupled to the secondarynetworked distribution system, the secondary networked distributionsystem providing electricity to a plurality of consuming endpoints; andin response to receiving the message, retransmitting, by the first ENCDon the secondary networked distribution system, the message to aplurality of internal node control devices communicatively coupled tothe secondary networked distribution system at a plurality of locations.2. The method of claim 1, wherein the first ENCD is located at a gridnode, the grid node housing an electrical control or monitoring (ECOM)device coupled to the secondary networked distribution system, andwherein the first ENCD is communicatively coupled to the ECOM device andis configured to, in response to receiving the message, send a signal tothe ECOM device to cause the ECOM device to alter or monitor anelectrical characteristic of the secondary networked distributionsystem.
 3. The method of claim 2, wherein the ECOM device comprises oneof a transformer, a switch, a fuse, or a monitoring device.
 4. Themethod of claim 1, wherein receiving, by the first ENCD via the off-gridcommunications interface, the message, further comprises: receiving, bya plurality of ENCDs, including the first ENCD, the messagesubstantially concurrently; and wherein retransmitting, by the firstENCD on the secondary networked distribution system, the message to theplurality of internal node control devices communicatively coupled tothe secondary networked distribution system at the plurality oflocations further comprises retransmitting, by the plurality of ENCDs onthe secondary networked distribution system, the message to theplurality of internal node control devices communicatively coupled tothe secondary networked distribution system at the plurality oflocations.
 5. The method of claim 1, further comprising determining thatthe plurality of internal node control devices received the message. 6.The method of claim 5, wherein determining that the plurality ofinternal node control devices received the message comprises receiving aplurality of acknowledgement messages via the secondary networkeddistribution system, each acknowledgement message being sent by one ofthe plurality of internal node control devices.
 7. The method of claim6, wherein determining that the plurality of internal node controldevices received the message further comprises determining that anegative acknowledgement message has not been received within apredetermined timeframe.
 8. The method of claim 1, further comprisingreceiving, by an internal node control device, the message, andretransmitting the message on the secondary networked distributionsystem.
 9. The method of claim 1, further comprising receiving, by aninternal node control device, the message, and transmitting, on thesecondary distribution network system an acknowledgement messageindicating the internal node control device received the message. 10.The method of claim 1, further comprising: receiving, by an internalnode control device, the message; determining that the message isdirected to the internal node control device; determining that themessage identifies an action to be performed by the internal nodecontrol device; and performing the action.
 11. The method of claim 10,further comprising: determining that the message identifies a futuretime when the action is to be performed; waiting until the future time;and performing the action.
 12. The method of claim 10, furthercomprising: determining that the message identifies a future event thatwill trigger the action to be performed; determining that the futureevent has occurred; and performing the action.
 13. The method of claim12, wherein the future event comprises a presence of a tone on thesecondary networked distribution system, and further comprising:listening to the secondary networked distribution system for thepresence of the tone; detecting the presence of the tone on thesecondary networked distribution system; and in response to detectingthe presence of the tone on the secondary networked distribution system,performing the action.
 14. The method of claim 1, wherein the message isaddressed to a first internal node control device of the plurality ofinternal node control devices and a second internal node control deviceof the plurality of internal node control devices, and the messageidentifies an action to be performed at a future time concurrently bythe first internal node control device and the second internal nodecontrol device.
 15. A system for communicating on a secondary networkeddistribution system, comprising: an edge node control device comprising:an on-grid communications interface configured to be communicativelycoupled to the secondary networked distribution system, the secondarynetworked distribution system configured to provide electricity to aplurality of consuming endpoints; an off-grid communications interfaceconfigured to communicate via an off-grid communications technology; anda first processing device communicatively coupled to the on-gridcommunications interface and the off-grid communications interface, andconfigured to: receive, via the off-grid communications interface, amessage; and in response to receiving the message, retransmit on thesecondary networked distribution system the message to a plurality ofinternal node control devices communicatively coupled to the secondarynetworked distribution system at a plurality of locations.
 16. Thesystem of claim 15, wherein the edge node control device furthercomprises: a communications interface configured to communicate with anelectrical control or monitoring (ECOM) device configured to be coupledto the second networked distribution system; and wherein the firstprocessing device is communicatively coupled to the communicationsinterface and is further configured to: in response receiving themessage, send a signal to the ECOM device to cause the ECOM device toalter or monitor an electrical characteristic of the secondary networkeddistribution system.
 17. The system of claim 15 further comprising aplurality of edge node control devices, wherein each edge node controldevice of the plurality of edge node control devices is configured to:receive the message substantially concurrently; and retransmit, on thesecondary networked distribution system, the message to the plurality ofinternal node control devices.
 18. The system of claim 15, furthercomprising: a computing device comprising: a communications interface;and a second processing device communicatively coupled to thecommunications interface and configured to: generate the message;transmit the message to the edge node control device; and determine thatthe plurality of internal node control devices received the message. 19.The system of claim 18, wherein to determine that the plurality ofinternal node control devices received the message the second processingdevice is further configured to receive a plurality of acknowledgementmessages via the secondary networked distribution system, eachacknowledgement message being sent by one of the plurality of internalnode control devices.